Relatively recently, the technology has developed for the incorporation of scent samples within the pages of printed matter. Advertisers have made Great use of this technology to publicize new perfumes, lotions, after shaves, etc; virtually any product which may be considered to have a pleasant scent. The process is known as scent microencapsulation, whereby the scent particles are encapsulated in a myriad of relatively impervious tiny capsules or bubbles which serve to enclose the scent until such time as it is released by breaking the microcapsules; hence the term, "Scratch And Smell" (.TM.).
However, in practice it has been found that the sealing of the scent by the microencapsulation process is generally less than perfect, and the odor of the scent incorporated into the printed matter (magazine, etc.) often permeates the surrounding area even when the scent microcapsules have not been deliberately damaged. Many persons find that the odor of many of these scent products, when combined with the odor of the fresh paper upon which the scent slurry has been applied, is rather objectionable and can be somewhat medicinal in fragrance, thus destroying the sensation which the advertisers intend to convey. Moreover, many persons are allergic to some of the natural or synthetic scent compounds used in this technology and would prefer to avoid any inhalation or contact with the material if at all possible.
The need arises for a more positive method of sealing such microencapsulated scent slurry in printed matter by means of an adhesively applied impervious sheet overlay, and an apparatus for providing such positive sealing. The apparatus must be capable of continuous operation in order to be compatible with the industrial printing process, and must be adaptable to current printing processes and machinery without need for extensive modification of the printing process. The method and apparatus may be applied to both sides of the scent slurry coated web, to more completely seal the scent and completely eliminate bleed-through of any scent and/or chemicals.